JP2014156659A - Sizing press machine - Google Patents

Abstract

A sizing press machine capable of stably holding a sintered body having a flange in a through-hole and smoothly performing a sizing process.
SOLUTION: A plurality of through holes are formed in a circumferential direction for accommodating a sintered product having a flange formed in a part in a thickness direction, and the sintered product is received at a sintered body supply stage and rotated around an axis. A sizing press machine having a turntable for moving to a sizing station where pressing by punching is performed, the holding unit 33 holding the sintered product, and the holding unit 33 connected to the holding unit 33 And a driving mechanism 50 for moving the holding part 33 forward and backward with respect to the inside of the through-hole, and the front end of the holding portion 33 is below the flange in the advanced state when the sintered product is stored in the through-hole. It is located and can move outward from the flange when retracted by the retracting means.
[Selection] Figure 8

Description

  The present invention relates to a sizing press machine that performs sizing by putting a sintered body of metal powder into a mold again and pressing it.

  When a sintered body requiring dimensional accuracy is produced, sizing may be further performed after a metal powder mixing process, a forming process, and a sintering process that are normally performed. In order to obtain a predetermined size, this sizing means that the sintered body is put into a mold again and compressed. For example, the sizing is generally performed by a sizing press machine as shown in Patent Document 1, for example.

  As shown in FIG. 9, the sizing press machine includes a turntable 1 that is rotated intermittently, and a sintered body is formed inside a through hole 1 a that is formed through the turntable 1 in the vertical direction. 120 is set. The sintered body 120 has a two-stage cylindrical shape in which a flange 120b projecting radially outward is formed at the end of the cylindrical portion 120a.

  The through hole 1a is provided with a plurality of ball bushes (holding portions) 3 biased by a spring or the like toward the inside of the through hole 1a, and the outer periphery of the flange 120b of the sintered body 120 is a ball. By being pressed by the bush 3, the sintered body 120 is held in the through hole 1 a. As a result, the sintered body 120 is fixed in the through hole 1a without rotating in the circumferential direction of the sintered body 120.

  And the sintered compact 120 set in this way is moved by intermittent rotation of the turntable 1, and sizing is given by receiving the press by the punch which is not shown in figure in a sizing station.

JP 7-197106 A

  By the way, in the sizing press machine, because of the configuration in which the flange 120b of the sintered body 120 is pressed and held by the urging force of the plurality of ball bushes 3, when the thickness of the flange 120b of the sintered body 120 is small, There was a problem that the holding of the sintered body 120 became unstable.

Moreover, in order to perform a sizing process smoothly, it is preferable that the holding | maintenance part holding the sintered compact 120 like the said ball bush 3 does not become obstructive of a press.
The present invention has been made in view of such a problem, and provides a sizing press machine capable of stably holding a sintered body having a flange in a through hole and smoothly performing a sizing process. With the goal.

In order to solve the above problems, the present invention proposes the following means.
The invention according to claim 1 is a sintered body supply stage in which a plurality of through-holes are formed in the circumferential direction for accommodating a sintered product having a flange formed in a part in the thickness direction in which powder metal is compacted and sintered. A sizing press machine including a turntable that receives the sintered product, rotates about an axis, and moves to a sizing station where punching is performed, and a holding unit that holds the sintered product; A drive mechanism connected to the holding portion and moving the holding portion forward and backward with respect to the inside of the through hole, and the tip of the holding portion advances when the sintered product is stored in the through hole. It is located below the flange in a state and is movable outward from the flange when retracted by the retracting means.

  The invention according to claim 2 is the sizing press machine according to claim 1, wherein the drive mechanism is an actuator.

  The invention according to claim 3 is the sizing press machine according to claim 1, wherein the drive mechanism is a ball screw mechanism.

  The invention according to claim 4 is the sizing press machine according to claim 1, wherein the drive mechanism is a cam.

  The invention according to claim 5 is the sizing press machine according to any one of claims 1 to 4, wherein the driving mechanism is configured to be driven independently of the punch. And

According to the sizing press machine according to the present invention, when the holding portion is in the advanced state, the tip of the holding portion is located below the flange of the sintered body. Thereby, when holding a sintered compact in a through-hole, the front-end | tip of a holding | maintenance part will contact | abut from the upper part to the flange of a sintered compact, and this flange will be in the state mounted on the holding | maintenance part.
As described above, the flange is placed on the tip of the holding portion, and the outer peripheral surface of the sintered body is pressed by the holding portion, so that the sintered body regardless of the thickness dimension of the flange of the sintered body. Can be stably held in the through hole.
Furthermore, when the sintered body is pressed, the holding part is retracted outward from the flange by the retracting means, so the presence of the holding part does not interfere with the press, and the sizing process by the press is performed. It can be done smoothly.
Furthermore, since the holding part advances and retreats with respect to the inside of the through-hole by the drive mechanism, the sizing process by the press is smoothly performed without the presence of the holding part hindering the press while reliably holding the workpiece. be able to.
In addition, since the holding portion can be rapidly advanced and retracted by the drive mechanism, the sintered body can be appropriately held particularly when the thickness of the sintered body is thin.

  The invention according to claim 6 is the sizing press machine according to any one of claims 1 to 5, wherein a rotating body that supports the sintered product is provided at a tip of the holding portion. A sizing press machine.

  According to the sizing press machine according to the present invention, the rotating body moves backward in the direction of the outer periphery while rotating in the moving direction of the sintered body, so that the sizing process by the press is smoothly performed. Can do.

  According to the sizing press machine of the present invention, the sintered body can be stably held in the through hole by holding the lower portion of the flange of the sintered body by the holding portion. Further, since the holding portion is retracted to the outside of the flange by the retracting means at the time of pressing, the presence of the holding portion does not hinder the pressing, and the sizing process can be performed smoothly.

It is a top view of the turntable of the sizing press machine which concerns on a 1st reference example. It is a longitudinal cross-sectional view of the sizing press machine in a sizing station. FIG. 3 is an enlarged view of the vicinity of a holding unit in FIG. 2. It is a longitudinal cross-sectional view of a sizing press machine in a sizing station during pressing. It is a figure explaining the 2nd reference example of an evacuation means. It is a figure explaining the 3rd modification of an evacuation means. It is a figure explaining the 4th reference example of an evacuation means. It is a figure explaining one Embodiment of an evacuation means. It is a longitudinal cross-sectional view of the conventional sizing press machine.

Hereinafter, a first reference example of the sizing press machine of the present invention will be described in detail with reference to the drawings.
The sizing press machine 10 of the first reference example conveys the sintered body 2 by the turntable 20 and performs a sizing process on the sintered body 2 by the press mechanism 40.

As shown in FIG. 2, the sintered body 2 subjected to the sizing treatment by the sizing press machine 10 of the first reference example has a cylindrical portion 2a centered on the axis O and a radially outer side from one end portion of the cylindrical portion 2a. It has a two-stage cylindrical shape including a flange 2b protruding from the bottom. The sintered body 2 is formed with a plurality of core holes 2c drilled in parallel with the axis O with a certain interval in the circumferential direction.
Such a sintered body 2 is formed by compacting and sintering a powder metal.

  The turntable 20 has a substantially disk shape, and is installed to be rotatable around a central axis C along the vertical direction. A plurality of slits 21 are formed on the outer periphery of the turntable 20 in parallel with the central axis C, that is, in the vertical direction and extending radially inward of the turntable 20 at equal intervals in the circumferential direction. ing.

  A drive mechanism 22 for intermittently rotating the turntable 20 is installed on the outer peripheral side of the turntable 20. The drive mechanism 22 includes a rotation axis P that is parallel to the central axis C of the turntable 20, and a cam 24 that extends radially outward is fixed to the rotation axis P.

Furthermore, a protrusion 24a is provided at the tip of the cam 24 so as to protrude downward. In the range of about 90 °, which is a part of a circular locus drawn by the protrusion 24a, the protrusion 24a is formed. The portion 24a is accommodated in the slit 21 of the turntable 20, and is in an escaped state from the slit 21 in the remaining 270 ° range.
In this way, the cam 24 turns in the rotational direction U on the horizontal plane at a constant rotational speed as the rotary shaft P rotates.

  Thus, when the drive mechanism 22 rotates around the rotation axis P at a constant speed, the rotation of the drive mechanism 22 is transmitted to the turntable 20 only when the protrusion 24a is housed in the slit 21, and the turn The table 20 is sent in the rotation direction T and rotates. On the other hand, when the protrusion 24a is in the escape state from the slit 21, only the cam 24 turns and the turntable 20 is stopped. In this way, the turntable 20 is intermittently rotated in the rotation direction T by the drive mechanism 22.

In such a turntable 20, a plurality of holes 12a (12 in the first reference example) are formed in the circumferential direction so as to extend circularly up and down along the outer periphery thereof.
A sintered body housing part 30 for housing the sintered body 2 is fitted in the hole 20a.

The sintered body accommodating portion 30 is a member having a substantially cylindrical shape centering on the axis O, and is fitted into the hole 20a so that both end openings are directed vertically as shown in FIG. Is a through hole 31 for housing the sintered body 2.
The inner diameter of the through hole 31 is formed substantially the same as the outer diameter of the flange 2 b of the sintered body 2.
Thereby, when the sintered body 2 is accommodated in the through hole 31, the flange 2 b of the sintered body 2 is arranged with a slight gap from the through hole 31.
The inner diameter of the through hole 31 is larger than the outer diameter of the flange 2 b of the sintered body 2, and when the sintered body 2 is stored in the through hole 31, a gap is formed between the through hole 31 and the sintered body 2. It may be formed.

  In such a sintered body accommodation portion 30, an accommodation hole 32 that penetrates the through hole 31 and the outer peripheral surface of the sintered body accommodation portion 30 is formed along the radial direction. A plurality (three in the first reference example) of the accommodation holes 32 are formed at equal intervals in the circumferential direction of the sintered body accommodation unit 30.

  Each storage hole 32 is provided with a holding portion 33 for holding the sintered body 2 in the through hole 31. As shown in detail in FIG. 3, the holding portion 33 includes a holding portion main body 36, an elastic body (biasing means) 37, and a rotating body (retracting means) 38.

  The holding part main body 36 is a member extending along the radial direction of the sintered body housing part 30, and an elastic body 37 is attached to the radially outer end of the sintered body housing part 30 in the holding part main body 36. A rotating body 38 is attached to the radially inner end of the sintered body housing 30.

  The elastic body 37 is an expandable member such as a spring coil, for example, and the end of the elastic body 37 opposite to the end attached to the holding portion main body 36 is the inner periphery of the hole 20a of the turntable 20. Supported by the surface. By this elastic body 37, the holding portion main body 36 is urged toward the inside in the radial direction of the sintered body accommodation portion 30, that is, toward the inside of the through hole 31.

  The rotating body 38 is a roller attached to the end of the holding unit main body 36 on the radially inner side of the sintered body housing portion 30 so as to be rotatable about an axis perpendicular to the radial direction of the sintered body housing portion 30. In addition, the elastic body 37 is caused to protrude radially inward from the inner peripheral surface of the through hole 31 of the sintered body accommodating portion 30 by the biasing of the elastic body 37.

When the turntable 20 including the sintered body accommodation unit 30 having the above-described configuration is intermittently rotated by the drive mechanism 22 and the sintered body accommodation unit 30 is positioned on the sintered body supply stage (not shown), The sintered body 2 is housed in the through hole 31 of the sintered body housing portion 30.
In this sintered body supply stage, the sintered body 2 is inserted into the through-hole 31 from above, and the rotating body 38 of the holding portion 33 contacts the outer peripheral surface of the cylindrical portion 2a of the sintered body 2 and the lower surface of the flange 2b. Touch. Thereby, the sintered body 2 is held in the through hole 31.

And when the sintered compact accommodation part 30 holding the sintered compact 2 moves to the sizing station (illustration omitted) by intermittent rotation of the turntable 20, the sizing process with respect to the sintered compact 2 is performed by the press mechanism 40. .
As shown in FIG. 2, the press mechanism 40 includes a punch 41, a die 43, and a punch receiving portion 45.

  The punch 41 is a member having a substantially cylindrical shape that reciprocates in the vertical direction and presses the sintered body 2 accommodated in the through-hole 31 from above. On the upper side, it is arranged coaxially with the axis O of the sintered body 2. The punch 41 is formed so that the outer diameter of the lower portion thereof is substantially the same as the inner diameter of the through-hole 31, and is inserted into the through-hole 31 through a slight gap when the punch 41 moves downward. It has come to be. By such a pressing operation of the punch 41, the sintered body 2 held in the through hole 31 is pushed downward.

  The punch 41 is provided with a plurality of core pins 41a extending downward at equal intervals in the circumferential direction. The core pins 41a are inserted into the core holes 2c of the sintered body 2 when the punch 41 is lowered. Thereby, the circumferential movement of the sintered body 2 when the punch 41 is lowered is restricted, and the positioning of the sintered body 2 during pressing can be performed reliably.

The die 43 is disposed below the sintered body accommodating portion 30 moved to the sizing station, and a die hole 44 penetrating vertically is formed.
The die hole 44 is arranged coaxially with the axis O of the sintered body 2 in the same manner as the punch 41. The upper opening of the die hole 44 is an enlarged portion 44a having the same inner diameter as the outer diameter of the flange 2b of the sintered body 2, and the lower side of the enlarged portion 44a is the enlarged portion 44a. Further, the diameter is reduced by one step, so that a reduced diameter portion 44b having an inner diameter substantially the same as the outer diameter of the cylindrical portion 2a of the sintered body 2 is formed. As a result, the sintered body 2 extruded downward from the through hole 31 by the punch 41 fits the flange 2b into the enlarged diameter portion 44a and the cylindrical portion 2a into the reduced diameter portion 44b without gaps.

The punch receiving portion 45 has a cylindrical shape and is arranged coaxially with the axis O of the sintered body 2, similarly to the punch 41 and the die hole 44.
The outer diameter of the upper portion of the punch receiving portion 45 is formed to be the same as the inner diameter of the reduced diameter portion 44 b of the die hole 44. Thereby, the upper part of the punch receiving part 45 is inserted into the die hole 44 from below, and the upper end of the punch receiving part 45 comes into contact with the lower end surface of the sintered body 2 fitted in the die hole 44.

When the sizing process is performed on the sintered body 2 by the press mechanism 40, the punch 41 moves downward to push the sintered body 2 from the sintered body accommodating portion 30 into the die hole 44 of the die 43. As shown in FIG. 4, the sintered body 2 is sandwiched between the punch 41 and the punch receiving portion 45 in the die hole 44 and is subjected to a load, so that the sintered body 2 is reshaped to a desired size. Is done. Then, after sizing is performed on the sintered body 2, the punch 41 is raised, the turntable 20 is intermittently rotated, and the new sintered body 2 is conveyed to the sizing station.
In this way, the sizing process is sequentially performed on the plurality of sintered bodies 2 by the vertical stroke of the punch 41 and the intermittent rotation of the turntable 20.

In the sizing press machine 10 configured as described above, the rotating body 38 at the tip of the holding portion 33 is positioned below the flange 2b of the sintered body 2 when the holding portion 33 is in the forward movement state. As a result, when the sintered body 2 is held in the through hole 31, the tip of the holding portion 33 comes into contact with the flange 2 b of the sintered body 2 from above, and the flange 2 b is the tip of the holding portion 33. It will be in the state mounted on the rotary body 38. FIG. Furthermore, since the holding portion 33 is biased toward the inside of the through hole 31 by the elastic body 37, the outer peripheral surface of the cylindrical portion 2 a of the sintered body 2 is pressed by the plurality of holding portions 33.
As described above, the flange 2b is placed on the rotating body 38 and the rotating body 38 presses the outer peripheral surface of the cylindrical portion 2a, so that the sintered body 2 is not affected by the thickness of the flange 2b. The bonded body 2 can be stably held in the through hole 31.

  Further, when the sintered body 2 moves downward by the lowering of the punch 41, the holding portion 33 is retracted toward the outside of the through hole 31, that is, radially outward of the through hole 31. The sizing process can be performed smoothly without hindering the press by the punch 41.

  That is, in the first reference example, when the sintered body 2 housed in the through hole 31 moves downward, the flange 2b of the sintered body 2 is a portion of the rotating body 38 on the radially inner side of the through hole 31. , The rotating body 38 is retreated to the outside in the radial direction of the through hole 31 according to the shape of its outer periphery while rotating. Accordingly, the holding portion 33 is retracted to the outside of the sintered body housing portion 30. Therefore, the sizing process by the press can be performed smoothly without the presence of the holding portion 33 hindering the press.

  The sizing press machine 10 which is the first reference example of the present invention has been described above, but the present invention is not limited to this and can be appropriately changed without departing from the technical idea of the present invention.

  In the reference example, the rotating body 38 is used as a retracting means for retracting the holding portion 33 to the outside in the radial direction of the sintered body housing portion 30. However, as the third reference example, the rotating body 38 is provided with the rotating body 38. Instead, an insertion hole 39 penetrating in the vertical direction may be formed in the holding portion 33, and a guide member 48 inserted into the insertion hole 39 may be attached to the punch 41.

That is, in this modification, as shown in FIG. 5, the holding portion 33 is formed with an insertion hole 39 penetrating in the vertical direction, and a part of the inner peripheral surface of the insertion hole 39 is directed downward. The inclined surface 39 a is inclined toward the radially inner side of the sintered body accommodating portion 30. Further, a communication hole 30 a is formed directly above the insertion hole 39 at the retracted position of the holding portion 33, and penetrates the upper surface of the sintered body accommodation portion 30 and the inner peripheral surface of the accommodation hole 32 along the vertical direction. .
Further, the holding portion 33 is in a forward state due to the urging of the elastic body 37, and the tip of the holding portion 33 is curved and protrudes from the inner peripheral surface of the through hole 31. In this state, only a part of the portion directly above the inclined surface 39a of the insertion hole 39 and the communication hole 30a overlap in the vertical direction.
Further, the guide member 48 is provided integrally with the punch 41 (not shown in FIG. 5) or as a separate body, and is arranged to extend downward from directly above the communication hole 30a.

  In such a modification, when the punch 41 descends to size the sintered body 2 in a state where the holding portion 33 protrudes from the inner peripheral surface of the through hole 31 and holds the sintered body 2, FIG. As shown to (a), the guide member 48 also falls and the front-end | tip of this guide member 48 is inserted in the communicating hole 30b.

Thereafter, when the punch 41 is further lowered, the tip of the guide member 48 is inserted into the insertion hole 39 that partially overlaps the communication hole 30 b, and the tip of the guide member 48 contacts the inclined surface 39 a of the insertion hole 39.
When the guide member 48 is further lowered in such a state that the tip of the guide member 48 and the inclined surface 39a are in contact with each other, the holding portion 33 is arranged on the outer side in the radial direction of the sintered body accommodating portion 30 according to the inclination of the inclined surface 39a. Retreat to. That is, the holding portion 33 is retracted to the outside of the through hole 31 by the lowering operation of the guide member 48. As a result, when pressing with the punch 41, the holding portion 33 can be retracted to the outside of the through hole 31, and a smooth sizing process can be performed. The lowering speed of the guide member 48 is preferably set larger than the lowering speed of the punch 41.

  As a third reference example, as shown in FIG. 6, a rotating body 38 similar to the reference example may be provided at the tip of the holding portion 33 of the second reference example. In this case, in addition to the holding portion 33 being retracted by the guide member 48, the flange 2b of the sintered body 2 presses the rotating body 38 downward during pressing to retract the holding portion 33. Can do. Therefore, the sizing process can be performed more smoothly without the presence of the holding portion 33 hindering the pressing by the punch 41.

  Further, as a fourth reference example, as shown in FIG. 7, the same guide member 48 as in the second reference example and the third reference example is provided, and the guide hole 48 formed in the holding portion 33 is rotated to the rear wall surface side. The structure which provided the body 38 may be sufficient. In this case, when the guide member 48 is lowered and inserted into the insertion hole 39, the guide member 48 presses the forward-side portion of the rotating body 38 downward. As a result, the rotating body 38 is retracted to the rear side of the through hole 31 according to the shape of its outer periphery while rotating. Therefore, also in the fourth reference example, the sizing process can be performed smoothly without the presence of the holding portion 33 hindering the press by the punch 41.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
One embodiment is different from the first to fourth reference examples in that the holding portion is advanced and retracted by a driving mechanism, and the other configuration is the same. In one embodiment, as shown in FIG. 8, the rear end side of the holding portion 33 is connected to a drive mechanism 50 such as an air cylinder, and the holding means 33 is advanced and retracted by driving of the drive mechanism 50. May be. In this case, the drive mechanism 50 is configured to serve as a retracting unit and an urging unit for the holding unit 33. The drive mechanism 50 may be a hydraulic cylinder, a ball screw mechanism, or the like in addition to an air cylinder.
In this embodiment, since the holding means 33 can be advanced and retracted quickly by arbitrarily driving the drive mechanism 50, the sintering is performed particularly when the thickness of the sintered body in the direction of the axis O is thin. It becomes possible to hold the body 2 accurately.

  Further, for example, as a means for retracting the holding portion 33, a control device such as a cam or an actuator that is driven independently of the stroke of the punch 41 and retracts the holding portion 33 may be provided.

2 Sintered body 2a Cylindrical portion 2b Flange 10 Sizing press machine 20 Turntable 20a Hole portion 21 Slit 30 Sintered body accommodation portion 31 Through hole 32 Accommodation hole 33 Holding portion 36 Holding portion main body 37 Elastic body (biasing means)
38 Rotating body (withdrawal means)
39 Insertion hole (withdrawal means)
39a Inclined surface 40 Press mechanism 41 Punch 48 Guide member (retracting means)
50 Drive mechanism

Claims (6)

A plurality of through-holes are formed in the circumferential direction to accommodate a sintered product in which a flange is formed in a part of the thickness direction in which powder metal is compacted and sintered, and the sintered product is received at a sintered body supply stage. , A sizing press machine with a turntable that rotates about an axis and moves to a sizing station where a punch press is performed,
A holding part for holding the sintered product;
A drive mechanism that is connected to the holding portion and moves the holding portion forward and backward with respect to the inside of the through hole;
With
The tip of the holding portion is positioned below the flange in the advanced state when the sintered product is stored in the through-hole, and moves outward from the flange when retracted by the retracting means. A sizing press machine characterized by being enabled. The sizing press machine according to claim 1,
The sizing press machine, wherein the drive mechanism is an actuator. The sizing press machine according to claim 1,
The sizing press machine, wherein the drive mechanism is a ball screw mechanism. The sizing press machine according to claim 1,
The sizing press machine, wherein the drive mechanism is a cam. A sizing press machine according to any one of claims 1 to 4,
The sizing press machine, wherein the drive mechanism is configured to be driven independently of the punch. A sizing press machine according to any one of claims 1 to 5,
A sizing press machine, wherein a rotating body that supports the sintered product is provided at a tip of the holding portion.

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